Refractory materials are fundamental to high-temperature technology. Their core function is to resist high temperatures, chemical corrosion, mechanical wear, and thermal shock. They are widely used in metallurgy, building materials, chemicals, energy, aerospace, and other fields. With the advancement of industrial technology, refractories have evolved from their traditional single-purpose function to high-performance, environmentally friendly, and intelligent materials, becoming key materials supporting the upgrading of high-temperature processes.
I. Core Application Areas and Typical Case Studies
1. Metallurgical Industry: The “Guardian” of Steelmaking
Blast furnaces and converters: Magnesia bricks and magnesia-carbon bricks (MgO-C bricks) are used to resist corrosion from molten iron and slag, with a service life of over 10 years.
Ladles and tundishes: A single lining of aluminum-magnesium castables (Al₂O₃-MgO) has a service life of 260 cycles, reducing refractory consumption to 1.78 kg per ton of steel.
New Trends in Hydrogen Metallurgy: Hydrogen-based vertical furnaces require the development of new refractories that resist hydrogen erosion, such as alumina-silicon carbide composite bricks, to meet the needs of low-carbon steelmaking.
2. Building Materials Industry: A High-Temperature Barrier Between Cement and Glass
Cement Rotary Kiln:
Firing Zone: Magnesium-Fe-Aluminum Spinel Bricks Replace Chrome-Containing Bricks, Addressing Hexavalent Chromium Pollution.
Transition Zone: Three-layer Composite Bricks (Working Layer + Insulation Layer + Heat-Insulating Layer) Reduce Cylinder Temperature by 60°C, Extending Lifespan to 3 Years.
Photovoltaic Glass Melting Furnace:
High-density zircon bricks (ZrO₂·SiO₂) are used for the tank walls and arches, offering a refractoriness of >1790°C, reducing the need for thermal repairs and increasing furnace life by 50%.
3. Energy and Chemical Industry: Challengers in Extreme Environments
Petrochemical Industry:
The lining of the catalytic cracking unit utilizes low-cement corundum castable, offering thermal shock resistance of over 100 cycles and extending the operating cycle to 2 years.
Coal-to-Hydrogen Converter:
Alumina hollow sphere castable (Al₂O₃ hollow sphere + refractory adhesive) is used in burners, offering a temperature resistance of 1800°C, resistance to acid and alkali corrosion, and a 30% reduction in construction cycle.
4. Emerging Fields: New Energy and Aerospace
Lithium Battery Material Sintering: Mullite fiber modules (Al₂O₃·SiO₂) are used in high-temperature furnaces, offering a thermal conductivity as low as 0.15 W/m·K and energy savings of 30%.
Aerospace Engines: Silicon nitride bonded to silicon carbide (Si₃N₄-SiC) is used in combustion chambers, offering high-temperature creep resistance exceeding 1600°C, meeting the requirements of ultra-high-temperature flight.
II. Material Properties and Selection Logic
1. Classification by Chemical Properties
Acidic materials (e.g., silica bricks): Suitable for acidic slag environments (e.g., glass melting furnaces).
Alkaline materials (e.g., magnesia bricks): Resistant to alkaline slag corrosion (e.g., steelmaking converters). Neutral materials (such as corundum bricks): Suitable for complex chemical environments (such as ceramic kilns).
2. Selection Based on Functional Requirements
Thermal Shock Resistance: Silicon carbide bricks (SiC) have a low thermal expansion coefficient and are suitable for kilns with frequent temperature fluctuations (such as waste incinerators).
Wear Resistance: Corundum mullite bricks (85% Al₂O₃) are used in high-wear areas (such as cement kiln openings).
Thermal Insulation: Alumina hollow sphere bricks have a thermal conductivity as low as 0.2 W/m·K and are used for furnace insulation.
III. Technological Innovation and Future Trends
1. Environmental Protection and Efficient Resource Utilization
Chromium-Free Technology: Magnesium-aluminum spinel bricks replace chromium-containing magnesia-chrome bricks, reducing hexavalent chromium pollution.
Waste Slag Recycling: Steel slag and ore slag are used as raw materials to produce high-aluminum homogenizing materials, reducing resource consumption.
2. Functionalization and Intelligence
Self-Healing Materials: Microencapsulated repair agents are added to automatically release repair substances when cracks occur, extending service life by 20%. Online Monitoring System: Embedded sensors monitor lining temperature and stress in real time, providing early warning of damage risks.
3. Lightweighting and Energy Saving
Microporous Lightweight Materials: Mullite insulation bricks with pore sizes <5μm reduce density by 40% and kiln energy consumption by 15%.
IV. Corporate Practices and Industry Value
As a refractory manufacturer, we are committed to providing customized solutions for our customers:
Standardized Products: We offer a full range of high-alumina bricks, magnesia-carbon bricks, and castables to meet the needs of conventional applications.
Customized Services: We develop high-purity oxide materials that are resistant to hydrogen corrosion for emerging fields such as hydrogen metallurgy and lithium battery sintering.
Engineering Support: We provide a one-stop “materials + technology” service from material selection to installation and maintenance, helping customers reduce costs and increase efficiency.
Refractory materials are not only a “firewall” for high-temperature industries but also a catalyst for technological advancement. Going forward, we will continue to promote material innovation and contribute to the greener and more intelligent nature of industry.
